Add support for handling OS permissions

Some of the RP default screens are linked to OS permissions. These are:

* location
* health
* activity recognition
* notifications
* ...

We should add an option to these screens for asking for OS permissions, so that when the user clicks "NEXT" the next thing that happens is that the OS permission screen is shown. In this way, the permission screen is shown "in context" where the purpose of using these permissions is explained. This is a requirement from both Apple and Google.

Note that there are different requirements from Apple vs. Google, and RP should somehow handle these differences gracefully by checking the current OS.

## Resources

* **Android** - [Request runtime permissions](https://developer.android.com/training/permissions/requesting)
* **iOS** - [Privacy](https://developer.apple.com/design/human-interface-guidelines/privacy)